Satellite communication questions

1. Which of the following is the first active satellite?

A. Echo

B. Telstar

C. Early Bird

(Answer)D. Sputnik I

2. Which of the following is the first commercial satellite?

A. Early Bird

(Answer)B. Telstar

C. Explorer

D. Courier

3. What is the first passive satellite transponder?

A. Sun

(Answer)B. Early Bird

C. Score

D. Moon

4. The first satellite to receive and transmit simultaneously

A. Intelsat

B. Agila

C. Syncorn

(Answer)D. Telstar I

5. A helical antenna is used for satellite tracking because of

(Answer)A. circular polarization

B. maneuverability

C. beamwidth

D. gain

6. Repeaters inside communications satellites are known as

A. Trancievers

(Answer)B. Transponders

C. Transducers

D. TWT

7. Considered as the unsolved problem in satellite system

A. Coverage

B. Cost

C. Access(Answer)

D. Privacy

8. ___________ is a satellite that rotates around the earth in a low-altitude elliptical or circular pattern.

A. Geosynchronous satellite

(Answer)B. Non synchronous satellite

C. Pro grade satellite

D. Retrograde satellite

9. Is the geographical representation of a satellite antenna radiation pattern

(Answer)A. Footprint

B. Spot

C. Earth

D. Region

10. The smallest beam of a satellite antenna radiation pattern

A. Zone beam

B. Hemispheric beam

(Answer)C. Spot beam

D. Global beam

11. A satellite beam that covers almost 42.4% of the earths surface.

A. Zone beam

B. Hemispheric beam

C. Spot beam

(Answer)D. Global beam

12. What is the frequency range of C-band?

A. 8.5 to 12.5 GHz

(Answer)B. 3.4 to 6.425 GHz

C. 12.95 to 14.95 GHz

D. 27.5 to 31 GHz

13. A satellite signal transmitted from a satellite transponder to earth’s station.

A. Uplink

(Answer)B. Downlink

C. Terrestrial

D. Earthbound

14. Collects very weak signals from a broadcast satellite

A. Helical antenna

(Answer)B. Satellite dish

C. LNA

D. TWT

15. What is a device that detects both vertically and horizontally polarized signals simultaneously?

(Answer)A. Orthomode transducer

B. Crystal detector

C. Optoisolator

D. Isomode detector

16. _________ detects the satellite signal relayed from the feed and converts it to an electric current, amplifies and lower its frequency.

A. Horn antenna

(Answer)B. LNA

C. Satellite receiver

D. Satellite dish

17. Is a loss of power of a satellite downlink signal due to earth’s atmosphere.

A. Atmospheric loss

(Answer)B. Path loss

C. Radiation loss

D. RFI

18. What height must a satellite be placed above the surface of the earth in order for its rotation to be equal to earth’s rotation?

A. 26,426.4 miles

B. 27,426.4 miles

C. 23,426.4 miles

(Answer)D. 22,426.4 miles

19. Point on the satellite obits closest to the earth.

A. Apogee

(Answer)B. Perigee

C. Prograde

D. Zenith

20. The earth area covered by a satellite radio beam.

A. Beamwidth

B. Bandwidth

(Answer)C. Footprint

D. Zone

21. What is the local oscillator (mixer) frequency of the satellite with an uplink frequency in GHz band?

A. 3500 MHz

B. 4500 MHz

(Answer)C. 2225 MHz

D. 2555 MHz

22. What kind of battery panels are used in some advance satellites

A. Germanium based panels

B. Silicon based panel

C. Galium Phosphate solar panel array

(Answer)D. Galium Arsenide solar panel array

23. Satellite engine uses

A. jet propulsion

(Answer)B. ion propulsion system

C. liquid fuel

D. solar jet

24. A satellite batter has more power but lighter.

(Answer)A. Lithium

B. Leclanche

C. Hydrogen

D. Magnesium

25. What kind of battery used by older satellites?

A. Lithium

B. Leclanche

(Answer)C. Hydrogen

D. Magnesium

<h3><em>SATELLITE COMMUNICATION Questions and Answers pdf ::</em></h3>

26. VSAT was made available in

(Answer)A. 1979

B. 1981

C. 1983

D. 1977

27. What band does VSAT first operate?

A. L-band

B. X-band

(Answer)C. C-band

D. Ku-band

28. The first Philippine Mabuhay satellite has how many channels?

(Answer)A. 30

B. 24

C. 48

D. 50

29. The first Philippine Agila I will have how many transponders.

(Answer)A. 36

B. 48

C. 24

D. 12

30. How may satellite orbital slots are requested by the Philippine Government from ITU?

A. 2

B. 4

(Answer)C. 6

D. 8

31. The location of AsiaSat I.

(Answer)A. 105.5˚ East

B. 151.5˚ East

C. 115.5˚ East

D. 170.5˚ East

32. AsiaSat I covers how many countries in Asia?

(Answer)A. 38

B. 10

C. 28

D. 15

33. The owner of AsiaSat 2 is

A. Asia Satellite Telecommunications Company (ASTC)

B. Japan Satellite System (JSAT)

(Answer)C. China Great Wall Industry Corporation

D. Singapore Satellite Commision

34. What is the approximate path loss from satellite-to-earth station?

A. 100 dB

B. 150 dB

C. 175 dB

(Answer)D. 200 dB

35. INTELSAT stands for

A. Intel Satellite

B. International Telephone Satellite

(Answer)C. International Telecommunications Satellite

D. International Satellite

36. The frequency of Ku band for satellite communications.

A. 6/4 GHz

(Answer)B. 14/11 GHz

C. 12/14 GHz

D. 4/8 GHz

37. A satellite cross-link means

A. Earth-to-satellite link

B. Satellite-to-earth link

(Answer)C. Satellite-to-satellite link

D. None of these

38. Earth station uses what type of antenna

A. Despun antenna

B. Helical antenna

C. Toroidal antenna

(Answer)D. Cassegrain antenna

39. What is the delay time for satellite transmission from earth transmitter to earth receiver?

(Answer)A. 0.5 s

B. 1.0 s

C. 5 ms

D. 0.25 ms

40. The bandwidth of C-band satellite frequency band in U.S.

A. 500 GHz

B. 1000 GHz

C. 1000 MHz

(Answer)D. 500 MHz

41. The most common device used as an LNA is

A. zener diode

(Answer)B. tunnel diode

C. IMPATT

D. Shockley diode

42. The radiation patterns of earth coverage antennas have a beamwidth of approximately

A. 21˚

B. 5˚

(Answer)C. 17˚

D. 35˚

43. A mobile satellite array has usually how many elements?

A. 6

B. 88

C. 12

(Answer)D. 14

44. In a typical mobile satellite array antenna if three elements are activated, how many elements are deactivated?

A. 3

(Answer)B. 11

C. 5

D. 9

45. What circuit is responsible in activating and deactivating adjacent antenna elements in a mobile satellite array?

(Answer)A. Radial divider

B. Divider/combiner

C. Radial combiner

D. Radial multiplexer

46. Most mobile satellite array uses ___________ in transforming 50 to 150 Ω impedance.

A. stub

B. balun

(Answer)C. quarter-wavelength transformer

D. microstrip tapers.

47. The switching from one element to the other element in a typical mobile satellite array.

A. Series

B. Radial

C. Matrix

(Answer)D. Shunt

48. A method of multiple accessing where a given RF channel bandwidth is divided inot smaller frequency band.

A. CDMA

B. ANIK-D

C. TDMA

(Answer)D. FDMA

49. What is the delay time for satellite transmissions from earth transmitter to earth receiver?

(Answer)A. 0.5 s

B. 1s

C. 5 ms

D. 0.25 s

50. As the height of a satellite orbit gets lower, the speed of the satellite _________.

(Answer)A. increases

B. decreases

C. remains the same

D. None of the above

<h4><span style="text-decoration: underline

ADDING PAGES TO A BLOGGER BLOG

Adding pages (aka: a navigation bar or menu bar) is a great way to organize your blog to make important information easily accessible to your readers.

Designer Blogs offers several types of navigation bars: a navigation bar with simple text links, a navigation bar with custom buttons, and a navigation bar with drop-down menu (click on links for examples). These navigation bars are customized to give your blog a unique & professional look and can be purchased through our accessories shop.

However, you may just want a basic, non-customized Blogger menu bar, so today we are sharing a tutorial that explains how to get pages and a basic navigation bar added to your Blogger blog all on your own!

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STEPS FOR ADDING PAGES TO YOUR BLOG:

Step 1: Log in to the Blogger blog you are wanting to add pages to and click on the “Pages” link.

Step 2: Click the “New Page” button.

Step 3: Type the page title (this will appear as a link on the navigation bar), add the page content and then click “Publish.” Note: make sure the page is published or it will not show on your navigation bar.

Step 4: After your pages are published, you need to add the Pages gadget to your layout to make the categories appear on your blog. Go back to “Layout” and click on “Add a Gadget” in the space underneath the header. Note: If you want your navigation bar placed on your sidebar, click on “Add a Gadget” in the sidebar space.

Step 5: Choose “Pages” from the list of gadget options.

Step 6: Drag and drop your pages to rearrange them in the order you want them to appear and then click “Save.”

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ADDING A WEB ADDRESS TO YOUR NAVIGATION BAR:

Step 1: You may want to add some web addresses or links to labels along with your blank pages. Click on the “Pages” gadget and choose “+ Add external link.”

Step 2: In the first box, type the title you want to appear in the navigation bar. In the Web address (URL) box, insert the web address you want to link to. Then click “Save.”

Now view your blog to see your new pages and navigation bar!

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FOR ADJUSTING LEFT ALIGNED NAVIGATION MENUS

If you have a blog template with a left aligned navigation menu and you would like to adjust the positioning of the links, follow the below steps.

Step 1: In your dashboard, click on the “Theme” link and then click on “Customize.”

Step 2: In the Blogger Theme Designer click on “Advanced.”

Step 3: In the “Advanced” tab, scroll down until you find “Add CSS.”

To add more space to the left side of the navigation bar, add the following code:

.PageList {text-align:left !important; padding-left: 20px; }

.PageList li {display:inline !important; float:none !important; }

You will see a preview of how the design will look with the changes. If you adjust the “20” to a larger number it will add more space. If you want less space adjust the “20” to a smaller number.

Adjust it as you want and then click “Apply to Blog” to save the changes.

Example:

To center the links, add the following code:

.PageList {text-align:center !important; }

.PageList li {display:inline !important; float:none !important; }

You’ll see a preview of the changes. If you are happy with the way it looks, click “Apply to Blog” to save the changes.

Example:

For any further customizations you might need made to your navigation bar, you can visit ouradd-on shop to purchase one of our navigation bar options.

Wireless Markup Language (WML)

Contents

1. Purpose of WML
2. System View:  Delivering WML via Internet
3. WML Syntax and Examples
4. Exercises
5. References

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1. Purpose of WML

Target of WML

Developers of  apps for wireless devices

Typical Devices

• Phones
• PDAs

Typical Device Characteristics

Small display

Limited input capability

Narrowband network connection

Limited memory

Limited CPU power

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2. System View:  Delivering WML via Internet

The normal web delivery of pages to HTML browsers looks like this (from [AEO]:

A gateway is used to do a protocol conversion when a doc is delivered from an origin server to a phone.  A protocol conversion also occurs (to use a compact binary version of HTTP).

What phones have WML browsers?

Click here to find out!

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3. WML Syntax and Examples

Document Model

Controls text presentation and layout

User interface is deck of cards

• Deck = HTML page
• User navigates through sequence of cards

WML file is prameterized -- instantiate with variables to save memory

Provides inter-card navigation and linking

Supports scriting

Event handling for navigation or script invocation

User Navigation Model

• Browser maintans stack of URLs giving history, just like web browser
• Three operations on stack:
1. Reset:  Set stack to contain current card only
2. Push:  Put new URL on stack
3. Pop:  Remove current URL; return to previous URL

The Prev button on the phone does a pop.

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Initial exercise:  Run the phone simulator

Start the WML phone simulator as follows:

Select Start->Programs->Course Software->UP.SDK3.2forWML->UP.Simulator

You should see a screen with three choices starting "Input Field"; if not enter the following in the text box to the right of "Go" at the top of the phone window:

file:\\c:/program files/unwired planet/upsdkw32/examples/wml/controls.wml

First, play with the user interface.  The main screen will show you three choices:

• Input Field
• Select List
• Multiple Choice

se the up/down arrows followed by the OK soft key to select each in turn.
The first shows you password entry.

• Use the "BACK" button to return to the main screen.
• Then choose "Select List" to see how to select one from a list of items.
• Use the "BACK button again to return to the main screen.
  |
• Then choose "Multiple Choice" and try selecting two or more items (or deselecting items) from the list of first names.
• Use the "BACK button again to return to the main screen.

After this, select "Open Configuration" from the "File" menu at the top of the window.  Try each style of phone.  Note the variety of screen sizes!

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First Example:  Hello World

This example illustrates a simple WML file containing one
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
   "http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
  <card>
    <p>
    Hello!
    </p>
  </card>
</wml>
Open a file named "test.wml", paste the above text into the file, and try the phone simulator on test.wml to see what results!

Exercise 1

Open a text editor. Create a WML file named "pizza.wml".  The file will evolve into a user interface for ordering pizzas.  We'll have a screen to welcome to user to your pizza store (give it a name), and then screens to order the topping, crust, etc., followed by a screen that summarizes for the user what they ordered.
As the first step, create in pizza.wml an initial screen that welcomes the user to your pizza store!
Start a second copy of the phone simulator and display your file as follows:

Select Start->Programs->UP.SDK3.2forWML->UP.Simulator

To enter your file name, click in the textbox displaying the URL and type "file:\\c:/b/pizza.wml", replacing c:/b with the actual drive letter and path of your file.

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Second Example

This example shows how to make the soft key change the display from one sceen to a second screen:

<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
   "http://www.wapforum.org/DTD/wml_1.1.xml"><wml>
  <card>
    <p>
      <do type="accept">
        <go href="#card2"/>
      </do>
    Hello!
    This is the first card...
    </p>
  </card>
  <card id="card2">
    <p>
    This is the second card.
    Goodbye!
    </p>
  </card>
</wml>

Exercise 2

Edit the file you created earlier named "test.wml", paste the above text into the file.  Change focus to the phone simulator; if it is still displaying the old file test.wml, just hit F9 to display the new content of test.wml!
Then modify pizza.wml to add a second card, telling the user to choose whether they are ordering a pizza or a sub.  (We'll see how to insert the list of toppings momentarily!)

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Third Example

Now let's see how to insert a list of selections into a WML file...

<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
   "http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
  <card id="NetworkClassMenu">
    <p>
      Network Device Status
        <select>
            <option onpick="#PrinterMenu">
              Network Printers
              </option>
            <option onpick="#Computer_Menu">
              Computers
              </option>
            <option onpick="#Routers_MenuItem">
              Routers
              </option>
        </select>
    </p>
  </card>
  <card id="PrinterMenu">
      <p>
        Network Printers
          <select>
            <option onpick="#HPLJ5A_stats">
              HP-LaserJet 5M
            </option>
            <option onpick="#LMOE310A_stats">
              Lexmark Optra-E310
            </option>
            <option onpick="#HP2500CM_stats">
              HP-2500 CM
            </option>
          </select>
      </p>
  </card>
</wml>

Exercise 3

Edit the file you created earlier named "test.wml", paste the above text into the file.  Change focus to the phone simulator; if it is still displaying the old file test.wml, just hit F9 to display the new content of test.wml!
Modify your second sceen to let the user pick a topping, and whichever is picked, goto screen #3, where the user picks a crust.  Make screen #3 go to a screen #4, which we'll fill in later.

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Fourth Example

              
The following code will display a screen with an input field generated by the <input> tag.  The attribute name="i1" assigns a variable.  Also, the <do> elements are a way to order the screen display (in contrast to onpick used in the Third Example).

<wml>
  <card id="main">
      <do type = "accept"  label = "hello">
        <go href = "#card2"/>
      </do>
    <p>
        Enter your name:
        <input name="i1" />
    </p>
  </card>
  <card id="card2">
      <do type = "prev"  label = "hi">
        <prev/>
      </do>
    <p>
        Hello $i1, how are you?
    </p>
  </card>
</wml>

Exercise 4

Edit the file you created earlier named "test.wml", paste the above text into the file.  Change focus to the phone simulator; if it is still displaying the old file test.wml, just hit F9 to display the new content of test.wml!  Note how the display is automatically set to alpha mode so that you can spell your name.
Modify screen 4 in pizza.wml to ask the user to enter their name and phone number, then in screen #5 echo back what they input.  Be sure you understand how to enter a name (consisting of letters) versus a phone number (consisting of numbers) when you run your example!

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Using UIML with WML

Here is a simple UIML file that generates a WML file displaying a couple of lines of text...

<?xml version="1.0"?>
<!DOCTYPE uiml PUBLIC
        "-//UIT//DTD UIML 2.0 Draft//EN"
        "UIML2_0d.dtd">
<uiml>
 <interface>
   <structure>
    <part name="WelcomePage" class="Wml">
      <part name="WelcomeCard" class="Card">
        <!-- Sub Menu ======================= -->
        <part name="IntroP" class="P">
          <part name="Introduction" class="RichText">
                <style>
                        <property name="bold">true</property>
                        <property name="wrap">true</property>
                        <property name="content">You have successfully converted UIML to WML!</property>
                </style>
          </part>
        </part>

        <part name="SigP" class="P">
          <part name="Signature" class="RichText">
                <style>
                        <property name="italic">true</property>
                        <property name="wrap">true</property>
                        <property name="content">Ready for more?</property>
                </style>
          </part>
        </part>
      </part>
    </part>
  </structure>
 </interface>
</uiml>

Try this example.

Copy folder uiml2wml-0.3a from the shared folder to your folder.  Set these environment variables:

• UIML2WML=<your-dir>\uiml2wml-0.3a
• PATH=%PATH%;<your-dir>\uiml2wml-0.3a\bin

Type "dir %uiml2wml%.  You should see directories like "docs", "examples".
Put the blue UIML code above into a file name wmltest.uiml.  CD to the directory containing that file.  Enter this:

u2w -indent wmltest.uiml

The output file wmltest.wml should have been created.  Display this file in your web browser.

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More Examples

Try out the other examples in the Unwired Planet\UPSDKW32\examples\wml file.

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5. References

• [WML] Wireless Application Protocol Wireless Markup Language Specification Version 1.1, Version 16-June 1999, http://www1.wapforum.org/what/technical/SPEC-WML-19990616.pdf
• [AEO] Wireless Application Proocol Wireless Application Environment Overview, Version 16-June-1999, http://www1.wapforum.org/what/technical/SPEC-WAEOverview-19990616.pdf
• Unwired Planet's phone and WML browser simulator, available from dev.phone.com.